Composite structural unit



Jan, 19 1926.

J. G. DONALDSON ET AL COMPOSITE STRUCTURAL UNIT Filed June 29 1923 IINVEN'I'ORS Patented Jan. 19, 1926.

UNITED STATES' 1,569,954 PATENT OFFICE,

JOSEPH G. DONALDSON AND HENRY L. COLES, OIihHAMILTON, OHIO, ASSIGNOBS TO-GUABDIAN METALS COMPANY, OF HAMILTON, OHIO, A CORPORATION 01: DELA-wnnn.

COMPOSITE STRUCTURAL UNIT.

Application filed June 29, 1928. Serial No. 848,410.

To all whom it may concern:

Be it known that we, JosErH G. DONALD- SON and HENRY L. Cones, bothcitizens of the United States, and residing'at Hamilton in the county ofButler and State of Ohio, have invented certain new and usefulImprovements in Composite Structural Units, of which the following is aspecification. 7

The object of this invention is to provide a composite structural unitsuitable for use, for example, in theconstruction of safes, vaults andthe like, the same being of a character to resist melting or oxidationas by the local application of high heat by means such as theoXy-acetylene torch, penetration by the drill, and other methods ofattack and entry. It has heretofore been proposed to form a compositesheet, plate or billet (hereinafter termed a plate) by firstconstructing a core of high heat resisting material and thenencompassing this in metal, referably of high heat conductivity, tofacilltate the dissipation of heat throughout the mass and away from thepoint of attack. Our presentinvention mvolves composite material of thisgeneral character, in which, however, additional safeguards are providedagainst. attack by any of the methods above mentioned.

In carrying out our invention, we employ, imprimis, a core of high heatreslstance, this being, in whole or in part, either of vitreousmaterial'or of metal or of combinations of both. Preferably such core isof such character as that when placed in a mold and the encompassingsheath material poured about it there will be a union of the sheath Imetal and the core,due to the alloying of the materials of which bothare composed over the contactin areas. A composite plate so formed mayave a single refractory core or a plurality of such cores, and these maybe arranged either in alignment or staggered, as desired. Also, underthis 1nvention, the capacity of a plate so formed for resisting attackis greatly increased by combining with the internal core or cores one ormore internal air-chambers suitably arranged, these not onlyfacilitating the dissipation of heat but functioning to protect the massas against the action of explosives and the like. Heat reaching an airchamber will radiate into the air in the chamber and thus becomedissipated. In the event of an first a core 1, of high heat resistingmaterial,

which may, as above stated, be of vitreous or metallic material or acombination of both. As an example of a vitreous material, We point tothe use of a material included within the zirconium group, this materialbeing preferably comminuted and melted in the presence of a suitablebinder. As an example of a metallic material, we point to the use ofhigh melting-point metals, such as tungsten, molybdenum, uranium,vanadium and the like, or combinations of one or more of these, togetherwith nickel or copper or both, and a small quantum of carbon. As anexample of a material partly v treous and partly metallic, we point tothe use of a core formed of one of the materials in the zlrconium groupcombined with a metal such as copper, chromium and the like, servlngpreferably as a binder for the vltreous material 4. and in additiontending to Increase the capacity for conducting heat readily away fromthe point of attack Such a core, as previously indicated, may be usedslngly or, where the total thickness of the plate to be formed willpermit, in greater number. such as two, three or four.

In practice, we prefer to mount the-core or cores (as by means ofchaplets) in a suitable mold and to pour around it the molten metal,such as iron, steel, copper and the like. Under this invention, however,we provide for an air-chamber or chambers within the plate, and this isaccomplished by also setting up in the mold a sand or other form;suitably spaced from the core and also secured in position as bychaplets. One way by which this can be done is to encasc molding sand ina suitable jacket, providing such jacket with a suitable vent throughwhich sand may, after the molding operation, be withdrawn. lihe jacket,which may be of any desired material, may remain a permanent part of theplate. After the core or cores and chamber form or forms have beenplaced and secured in the mold, the molten metal may be flowed aroundthe same, care being observed that the vent or vents for the chambermold or molds be not covered, whereupon, not only will the core or coresbe: rigidly and permanently united to' the sheath-metal, as by alloyingtherewith, but provision will be made for a chamber or chambers for thepurpose above indicated. After the plate shall have cooled, the moldingsand may be removed and the rent or vents provided therefor permanentlyclosed by means of plugs or the like, as is well understood in theart,whereupon, a plate will result having in high degree the resistantqualities above mentioned. Not only may there be one or more cores,either vitreous or metallic or both, but there may also be one or moreair-chambers 2, and such cores and chambers may be alternate throughoutthe mass of the plate, it being preferred, however, that the sheathmaterial shall be of abundant mass outside of and beyond either or boththe core or cores and the chamber or chambers.

For the purpose of increasing the difficulty of penetration by heatattack when assisted by the fluxing rod; and also for the furtherpurpose of increasing the difiiculty of attack by drill, the core 01'cores, whether employed in conjunction with a chamber or not, may bedisposed within the mass of sheath material at an angle to the surfaceor surfaces thereof. The plate itself may also be set at an angle andthe core or cores may or may not be parallel to the surface thereof.

Attack by means of acetylene torches, when assisted by the fluxing rod,has been found most effective when a pocket can be formed in themetalwhich pocket can be filled with molten iron and a jet of oxygenplayed thereon. Under such circumstances, the molten iron will oxidizefreely, thus producing a great heat. The molten iron also has a greattendency to pass into solution with the metal attacked and thus greatlyassist in the disintegration or penetration thereof. However, if theplate is placed at an angle, it is difiicult to form a pocket in themetal attacked, inasmuch as'the molten metal dripping from the burningfluxing rod, will wash away the metal attacked in such a manner as tomake itdifficult to form a pocket.

Such a construction is illustrated in Figure 4 and the plate may or maynot be made with an air chamber or a plurality of air chambers, or witha core or plurality of cores.

Figure 3 illustrates an internal core without, however, an air chamberor chambers which, nevertheless, may be employed in this arrangement.

The sloping or inclining core will also turn a drill sideways when thesame penetrates into the plate perpendicular to the surface thereof.Also, when attack is made by a fluxing rod'against such a plate, the rodhas a tendency to slide along the core rather than to penetrate same.

It is not essential that in employing this invention the plate, so faras concerns the sheath material, be a strictly integral mass, as it mayconveniently and effectively be made up of two or more sectionspermanent ly united together in an suitable manner. Such a constructionis lllustrated in Figure 2, in which, as will be seen, the unit isformed in three sections, 3, 4 and 5, each of these in thisconstruction, having an internal core 1, and the core of the centralsection being, in this instance, angularly disposed with respect to theoutermost faces of the adjacent sections 3 and 5. Also, in thisinstance, the central section is provided in one face with an airchamber 2 and a' section 5 in one face with a similar air chamber, itbeing noted that in the case of the chamber fiist named the bottomthereof extends at an angle relatively to the external faces of theouter sections 3 and 5, the purpose here being the same as that ofangularly mounting a core or cores as explained above. In thisconstruction, thev sections may be separately cast and then, after theremoval of the core material, joined into a practically integral plate,as by welding the adjoining surfaces together.

While we prefer to form the air-chamber or chambers in the sheathmaterial, it is apparent that if desired the same may be formed in thecore material, where it or they will accomplish practically the sameresult.

As many changes could be made inthe above construction and as manydifferent embodiments of this invention could be made without departingfrom the scope thereof, it is intended that all matter contained in theabove description or shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

- Having now described our invention what we claim and desire to secureby Letters Patent is as follows 2-- v 1. As a new article ofmanufacture, a core of high heat resisting material, sheath materialassociated therewith, and an air-chamber formed within the compositemass so and an air-chamber formed withinthe composite mass soconstituted.

3. As a new article of manufacture, a core of high heat resistingmaterial, sheath material associated therewith, and a plurality ofair-chambers formed within the composite mass so constituted.

a. As a new article of manufacture, a plurality of cores of high heatresisting ma terial, sheath material associated therewith, and aplurality of air-chambers formed within the composite mass soconstituted.

5. As a new article of manufacture, a core of high heat resistingmaterial and sheath material associated therewith, said core beingangularly disposed with respect to the outer face of said sheathmaterial.

6. As a new article of manufacture, a core of high heat resistingmaterial, sheath material associated therewith, and an air-chamberformed within the composite mass so constituted, a face of said chamberbeing angularly disposed with respect to the outer face of said sheathmaterial.

7 As a new article of manufacture, a core of high heat resistingmaterial such as .an alloy of tungsten, nickel and carbon,

sheath material for said core, and an airch-amber formed within thecomposite mass so constituted.

8. As a new article of manufacture, a plurality of cores of high heatresisting material such as an alloy of tungsten, nickel and carbon,sheath material for said cores, and an air-chamber formed within thecomposite 'mass so constituted.

alloy of tungsten, nic el and carbon,'sheath I material for said core,and a plurality of air-chambers formed within the composite mass soconstituted.

10. As a new article of manufacture, a plurality of cores of high heatresisting ma terial such as an alloy of tungsten, nickel and carbon,sheath material for said cores, and a plurality of air-chambers formedwith in the composite mass so constituted.

11. As a new article of manufacture, a core of high heat resistingmaterial and sheath material associated therewith, said plate thusformed being an ularly disposed with respect to the perpen icular.

12. As a new article of manufacture, a plate composed of a core of highheat re sisting material and sheath material associated therewith, setat an angle to the perpendicular, said late containing an air chamberformed within the composite mass.

13. As a newarticle of manufacture, a plate composed of a core of highheat resisting material and sheath material associated therewith, set atan angle to the perpendicular, said plate containing a plurality of airchambers formed Within the composite mass so constituted.

This specification signed this 31 day of May, 1923.

' JOSEPH G. DONALDSON.

HENRY L. COLES.

